The Gulf of Mannar Marine National Park is a protected area of India consisting of 21 small islands (

islet An islet is a very small, often unnamed island. Most definitions are not precise, but some suggest that an islet has little or no vegetation and cannot support human habitation. It may be made of rock, sand and/or hard coral; may be permanen ...

s) and adjacent

coral reef A coral reef is an underwater ecosystem characterized by reef-building corals. Reefs are formed of Colony (biology), colonies of coral polyp (zoology), polyps held together by calcium carbonate. Most coral reefs are built from stony corals, wh ...

s in the

Gulf of Mannar The Gulf of Mannar ( ) is a large shallow bay forming part of the Laccadive Sea in the Indian Ocean with an average depth of .

in the

Indian Ocean The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or ~19.8% of the water on Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia to the east. To the south it is bounded by ...

. It lies 1 to 10 km away from the east coast of

Tamil Nadu Tamil Nadu (; , TN) is a state in southern India. It is the tenth largest Indian state by area and the sixth largest by population. Its capital and largest city is Chennai. Tamil Nadu is the home of the Tamil people, whose Tamil language ...

, India for 160 km between

Thoothukudi Thoothukudi (formerly Tuticorin) is a port city, a municipal corporation and an industrial city in Thoothukudi district in the Indian state of Tamil Nadu. The city lies in the Coromandel Coast of Bay of Bengal. Thoothukudi is the capital and he ...

(Tuticorin) and

Dhanushkodi Dhanushkodi is an abandoned town at the south-eastern tip of Pamban Island of the state of Tamil Nadu in India. It is south-east of Pamban and is about west of Talaimannar in Sri Lanka. The town was destroyed during the 1964 Rameswaram cycl ...

. It is the core area of the Gulf of Mannar Biosphere Reserve which includes a 10 km buffer zone around the park, including the populated coastal area. The park has a high diversity of plants and animals in its

marine Marine is an adjective meaning of or pertaining to the sea or ocean. Marine or marines may refer to: Ocean * Maritime (disambiguation) * Marine art * Marine biology * Marine debris * Marine habitats * Marine life * Marine pollution Military ...

intertidal The intertidal zone, also known as the foreshore, is the area above water level at low tide and underwater at high tide (in other words, the area within the tidal range). This area can include several types of habitats with various species ...

and near

shore A shore or a shoreline is the fringe of land at the edge of a large body of water, such as an ocean, sea, or lake. In physical oceanography, a shore is the wider fringe that is geologically modified by the action of the body of water past a ...

habitats In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

. Public access inside the park is limited to glass-bottom boat rides. It was established as a National Park in 1986.

Geography

The park is part of the 140 km long and 25 km wide Mannar

barrier reef A coral reef is an underwater ecosystem characterized by reef-building corals. Reefs are formed of colonies of coral polyps held together by calcium carbonate. Most coral reefs are built from stony corals, whose polyps cluster in groups. ...

. It lies between 8° 47' to 9° 15' N latitude and 78° 12' to 79° 14' E longitude. The 21 islands vary from 0.25 ha (.6 acre) to 130 ha. (321.2 acres). The total area of the islands is . The islands (listed southwest to northeast)

Tuticorin Thoothukudi (formerly Tuticorin) is a port city, a municipal corporation and an industrial city in Thoothukudi district in the Indian state of Tamil Nadu. The city lies in the Coromandel Coast of Bay of Bengal. Thoothukudi is the capital and ...

group: (4 islands)
Vaan, 16.0 ha
Koswari, 19.50 ha
Vilanguchalli, 0.95 ha , now 1 m below mean low tide level as a result of excessive coral mining.
Kariyachalli, 16.46 ha Vembar group: (3 islands)
Uppu Thanni, 22.94 ha, elevation 4 m
Puluvini Challi, 6.12 ha, elevation 5.5 m
Nalla Thanni, 101.00 ha, elevation 11.9 m (recently populated) Kilakarai group: (7 islands)
Anaipar, 11.00 ha, elevation 2.1 m
Vali Munai, 6.72 ha, elevation 1.2 m
Poovarasan Patti, 0.50 ha, elevation 1.2 m
Appa, 28.63 ha, elevation 6.4 m
Talairi, 75.15 ha, elevation 2.7 m
Valai 10.10 ha, elevation 3.0 m
Mulli, 10.20 ha, elevation 1.2 m AMS-Gulf of Mannar (SW)

Mandapam group:(7 islands)
Musal, 124.00 ha, elevation 0.9 m (recently populated)
Manoli, 25.90 ha
Manoli-Putti 2.34 ha
Poomarichan 16.58 ha
Pullivasal, 29.95 ha
Kurusadai, 65.80 ha was recently populated. Its surrounding shallow waters harbour three species of seagrass that are found nowhere else in India. Representatives of every animal phylum known (except amphibians) are found on this island.
Shingle, 12.69 ha, elevation .6m Tidal amplitude in the area is about .5m. There were two more islands named Pandayan and Punnaiyadi at that were destroyed for construction of the new Tuticorn Port facilities.

Flora

The park includes marine components such as

seaweed Seaweed, or macroalgae, refers to thousands of species of macroscopic, multicellular, marine algae. The term includes some types of '' Rhodophyta'' (red), ''Phaeophyta'' (brown) and '' Chlorophyta'' (green) macroalgae. Seaweed species such as ...

communities,

sea grass Seagrasses are the only flowering plants which grow in marine environments. There are about 60 species of fully marine seagrasses which belong to four families (Posidoniaceae, Zosteraceae, Hydrocharitaceae and Cymodoceaceae), all in the or ...

es, and

mangrove A mangrove is a shrub or tree that grows in coastal saline or brackish water. The term is also used for tropical coastal vegetation consisting of such species. Mangroves are taxonomically diverse, as a result of convergent evolution in severa ...

s. Mangroves dominate the intertidal zones of the park islands. They consist of species of the genera ''

Rhizophora ''Rhizophora'' is a genus of tropical mangrove trees, sometimes collectively called true mangroves. The most notable species is the red mangrove (''Rhizophora mangle'') but some other species and a few natural hybrids are known. ''Rhizophora'' ...

'', '' Avicennia'', '' Bruguiera'', ''

Ceriops ''Ceriops'' is a genus of mangroves in family Rhizophoraceae. There are 5 accepted species and 17 known synonyms. List of species * ''Ceriops australis'' (C.T.White) Ballment, T.J.Sm. & J.A.Stoddart ** ''Ceriops tagal'' var. ''australis'' C.T ...

'' and '' Lumnitzera''. The introduced tree genus '' Prosopis'' is dominant on land in all the islands. The flowering herb ''

Pemphis acidula ''Pemphis acidula'', commonly known as bantigue (pron. ) or mentigi, is a species of flowering plant in the family Lythraceae. It is a mangrove found throughout most of the tropical Indo-Pacific growing on rocky shores. The genus '' Pemphis'', to ...

'' (family

Lythraceae Lythraceae is a family of flowering plants, including 32 genera, with about 620 species of herbs, shrubs, and trees. The larger genera include ''Cuphea'' (275 spp.), ''Lagerstroemia'' (56), ''Nesaea'' (50), ''Rotala'' (45), and ''Lythrum'' (35). ...

) is the only endemic plant species. 12 species of sea grass and 147 species of seaweeds were recorded. This vegetation provides important feeding grounds for vulnerable marine mammals such as the

dugong The dugong (; ''Dugong dugon'') is a marine mammal. It is one of four living species of the order Sirenia, which also includes three species of manatees. It is the only living representative of the once-diverse family Dugongidae; its closest m ...

endangered An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and in ...

green turtle The green sea turtle (''Chelonia mydas''), also known as the green turtle, black (sea) turtle or Pacific green turtle, is a species of large sea turtle of the family Cheloniidae. It is the only species in the genus ''Chelonia''. Its range exten ...

s and olive ridley turtles.

Fauna

Vertebrates The dugong, a vulnerable

marine mammal Marine mammals are aquatic mammals that rely on the ocean and other marine ecosystems for their existence. They include animals such as seals, whales, manatees, sea otters and polar bears. They are an informal group, unified only by their ...

, is the flagship mammal of the park. It is an important habitat for the

cetacean Cetacea (; , ) is an infraorder of aquatic mammals that includes whales, dolphins, and porpoises. Key characteristics are their fully aquatic lifestyle, streamlined body shape, often large size and exclusively carnivorous diet. They propel th ...

Indo-Pacific bottlenose dolphin The Indo-Pacific bottlenose dolphin (''Tursiops aduncus'') is a species of bottlenose dolphin. This dolphin grows to long, and weighs up to . It lives in the waters around India, northern Australia, South China, the Red Sea, and the eastern ...

finless porpoise ''Neophocaena'' is a genus of porpoise native to the Indian and Pacific oceans, as well as the freshwater habitats of the Yangtze River basin in China China, officially the People's Republic of China (PRC), is a country in East Asia. ...

, spinner dolphin,

common dolphin The common dolphin (''Delphinus delphis'') is the most abundant cetacean in the world, with a global population of about six million. Despite this fact and its vernacular name, the common dolphin is not thought of as the archetypal dolphin, wi ...

Risso's dolphin Risso's dolphin (''Grampus griseus'') is a dolphin, the only species of the genus ''Grampus''. Some of the closest related species to these dolphins include: pilot whales (''Globicephala'' spp.), pygmy killer whales (''Feresa attenuata''), melon ...

, melon-headed whale, and dwarf sperm whale. Larger whales include

sperm whale The sperm whale or cachalot (''Physeter macrocephalus'') is the largest of the toothed whales and the largest toothed predator. It is the only living member of the genus ''Physeter'' and one of three extant species in the sperm whale famil ...

, minke whale,

Bryde's whale Bryde's whale ( Brooder's), or the Bryde's whale complex, putatively comprises three species of rorqual and maybe four. The "complex" means the number and classification remains unclear because of a lack of definitive information and research. ...

sei whale The sei whale ( , ; ''Balaenoptera borealis'') is a baleen whale, the third-largest rorqual after the blue whale and the fin whale. It inhabits most oceans and adjoining seas, and prefers deep offshore waters. It avoids polar and tropical w ...

, and critically endangered species including

humpback whale The humpback whale (''Megaptera novaeangliae'') is a species of baleen whale. It is a rorqual (a member of the family Balaenopteridae) and is the only species in the genus ''Megaptera''. Adults range in length from and weigh up to . The hu ...

fin whale The fin whale (''Balaenoptera physalus''), also known as finback whale or common rorqual and formerly known as herring whale or razorback whale, is a cetacean belonging to the parvorder of baleen whales. It is the second-longest species of ceta ...

, and

blue whale The blue whale (''Balaenoptera musculus'') is a marine mammal and a baleen whale. Reaching a maximum confirmed length of and weighing up to , it is the largest animal known to have ever existed. The blue whale's long and slender body can ...

. About 510 (23%) of the 2,200 fin fish species in Indian waters are found in the Gulf, making it the most highly diverse fish habitat in India. Coral associated ornamental fishes of the family Chaetodontidae (

butterfly fish The butterflyfish are a group of conspicuous tropical marine fish of the family Chaetodontidae; the bannerfish and coralfish are also included in this group. The approximately 129 species in 12 genera are found mostly on the reefs of the At ...

), parrotfish, '' Amphiprion'' spp. (

clown fish Clownfish or anemonefish are fishes from the subfamily Amphiprioninae in the family Pomacentridae. Thirty species of clownfish are recognized: one in the genus ''Premnas'', while the remaining are in the genus ''Amphiprion''. In the wild, the ...

), ''

Holocentrus ''Holocentrus'' is a genus of squirrelfishes found in the Atlantic Ocean. Species There are currently two recognized species in this genus: * ''Holocentrus adscensionis'' (Osbeck Pehr Osbeck (1723 – 23 December 1805) was a Swedish explor ...

'' spp. (squirrel fish), ''Scarus'' spp. ( parrot fish), ''Lutjanus'' spp. (snappers) and ''Abudefduf saxatilis'' ( sergeant major) are abundant. A unique endemic species of Balanoglossus – Ptychodera fluva, a living fossil that links invertebrates and vertebrates, has been recorded only at Kurusadai. Invertebrates Four species each of

shrimp Shrimp are crustaceans (a form of shellfish) with elongated bodies and a primarily swimming mode of locomotion – most commonly Caridea and Dendrobranchiata of the decapod order, although some crustaceans outside of this order are ref ...

and

lobster Lobsters are a family (Nephropidae, synonym Homaridae) of marine crustaceans. They have long bodies with muscular tails and live in crevices or burrows on the sea floor. Three of their five pairs of legs have claws, including the first pair, ...

, 106 species of

crab Crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" (abdomen) ( el, βραχύς , translit=brachys = short, / = tail), usually hidden entirely under the thorax. They live in all th ...

, 17 species of

sea cucumber Sea cucumbers are echinoderms from the class Holothuroidea (). They are marine animals with a leathery skin and an elongated body containing a single, branched gonad. Sea cucumbers are found on the sea floor worldwide. The number of holothuri ...

, and 466 species of

mollusc Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is est ...

including 271

gastropod The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, from freshwater, and from land. T ...

s, 174

bivalve Bivalvia (), in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class (biology), class of marine and freshwater Mollusca, molluscs that have laterally compressed bodies enclosed by a shell consisting of two hing ...

s, 5 polyplacophorans, 16

cephalopod A cephalopod is any member of the molluscan class Cephalopoda ( Greek plural , ; "head-feet") such as a squid, octopus, cuttlefish, or nautilus. These exclusively marine animals are characterized by bilateral body symmetry, a prominent head ...

s and 5 scaphopods, 108 species of

sponge Sponges, the members of the phylum Porifera (; meaning 'pore bearer'), are a basal animal clade as a sister of the diploblasts. They are multicellular organisms that have bodies full of pores and channels allowing water to circulate throu ...

, and 100 species of

echinoderm An echinoderm () is any member of the phylum Echinodermata (). The adults are recognisable by their (usually five-point) radial symmetry, and include starfish, brittle stars, sea urchins, sand dollars, and sea cucumbers, as well as the ...

occur in the Gulf. The coral fauna includes 106 species from 30 genus of hermatypes and 11 species from 10 genus of ahermatypes, including 13 new species, giving a total of 117 species from 14 families and 40 genus. The reefs in this area are narrow

fringing reef A fringing reef is one of the three main types of coral reef. It is distinguished from the other main types, barrier reefs and atolls, in that it has either an entirely shallow backreef zone (lagoon) or none at all. If a fringing reef grows dire ...

s located 150 to 300 m. from the shore of the islands and patch reefs rising up from depths of 2 to 9 m. and extending up to 2 km. long and 50 m. wide. Large areas of these reefs are in generally poor condition due to destructive human activities of the 150,000 persons living along the coast. Nutrient and other pollution loads are high due to agriculture, deforestation, industry, urbanization and septic pollution. It appears that the coral reefs of the Gulf of Mannar Marine National Park seem to be healthy and in good condition, despite high rates of sedimentation and other threats. However, live coral cover is only about 35%. Various algae cover much of the dead coral.

Stony coral Scleractinia, also called stony corals or hard corals, are marine animals in the phylum Cnidaria that build themselves a hard skeleton. The individual animals are known as polyps and have a cylindrical body crowned by an oral disc in which a mo ...

species of families Poritidae and

Faviidae Mussidae is a family of stony coral in the order Scleractinia. Following a taxonomic revision in 2012, the family is now restricted to species found in the Atlantic Ocean, with Pacific species transferred to the new family Lobophylliidae. Many ...

constitute the dominant reef builders here. Coral reefs near some of the islands have been heavily damaged by exploitation as raw materials for industrial ventures such as cement industries, brick manufacture, masonry work and lime kilns. Though legal quarrying of the reefs is now stopped, up to 250 m³/day of reef were destroyed for many years.

Habitation

The islands are uninhabited except for Krusadai, Musal and Nallathanni islands where antipoaching sheds are operating. Along the coast near the park there are about 125 villages which support about 100,000 people who are mainly Marakeyars, a local community principally engaged in fishing.

Habitat degradation

Experts say that Vaan Island, one of the four islands of the Tuticorn group, has split in two and if immediate efforts are not taken then the island would soon vanish under the sea. Vaan Island, which is the southernmost of the 21 islands in the Gulf of Mannar, was initially spread across 16 hectares, but had shrunk alarmingly by around 10.3 hectares to its current 5.7 hectares in less than three decades. According to J K Patterson Edward, director of Suganthi Devadasan Marine Research Institute (SDMRI), Tuticorin,"Rampant coral mining by people of the fishing villages along the coast is the main cause of the devastation to the island. Coral mining was banned in 2005, but the damage had already been done." Two of the 21 islands have already submerged around a decade ago.

Visitor information

Glass-bottomed boats available at Mandapam cater to tourists visiting the area. Access to the islands is prohibited. The nearest railway stations are at Mandapam and Tuticorin.

Geography

Flora

Fauna

Habitation

Habitat degradation

Visitor information

See also

References

Further reading